evaluation of mcnpx and gate with hotspot for internal dosimetry (simulation study)

objective: different categories are available for estimating of radiation dose. radioisotopes with the same energy and almost the same physical properties have similar effects. monte carlo technique is a computerized method based on mathematical simulation of physical processes. the main purpose of this study is to show that beta particles are not able to penetrate deep into the water. also difference between  gate and mcnp code is not significant. methods: in this study, a digital form of the cylinder mathematical phantom was constructed and used with gate and mcnpx to calculate the phantom dose. the voxel-based anthropomorphic zubal phantom was used to model a typical adult male. the equivalent effective dose derived for the electrons of er-169, p-32, and y-90 with gate and mcnpx. the results were compared to the hotspot data. results: the gate and mcnpx difference was negligible. however, difference at this level is acceptable and we can conclude that gate produces almost similar results as mcnpx. in this study, we tried to set the physical framework, calculate the penetration depth via dosimetry, using the results of the two simulator codes. in the first part, we applied the results of the hotspot dosimetry software for validation.conclusion: the gate and mcnpx difference was negligible.